The longer it goes on the worse I feel but the easier it gets to go longer periods without contact. I avoid my dad mostly and never feel guilty about it at all. I do a phone call and duty visit a few times a year to get it over with but that's easy as he lives far away.
I don't feel close to my parents I feel burdened by them. They are divorced but similar in opposing ways - sounds odd but as they age, they both seem to continue to use me to listen to their stories of bad health and woe. It's boring. They don't bring much positive to my life.
I had a complicated abusive childhood, I don't forgive either of them for their part in it. They expect me to. Dad does not want to discuss it or minimises his part (the worst part) but mother actually seems to revel in it - discussing in detail as if she too, suffered along side me 
As I said, as they age their only conversations are about bad things - ill health and repetitive stories about people from work I don't know.
But I do feel some residual guilt. I know my mother is very lonely and misses me terribly. I also feel unwillingly guilty for the fact I find her so boring and annoying. She lives nearby and I should visit more. My kids find her dull and irritating as well (worry they get this from me but they are teens now) and complain if I make them go there.
I kind of wish I felt differently, that I could want to visit and chat on the phone. She used to be very clingy but detachment has improved this. She makes the effort once a week to try to contact me and I always brush her off 'yeah I will see if I am busy' then forget about her.
Writing this I am not sure if I am a giant bitch or just that our relationship is too badly damaged. I would feel upset if something happened to her.
I suppose I want a better relationship but I don't know how to make one. Time I spent with her I can't wait to leave! Anyone in the same boat? How did it improve?